1
|
Abstract
Mosaicism—the existence of genetically distinct populations of cells in a particular organism—is an important cause of genetic disease. Mosaicism can appear as de novo DNA mutations, epigenetic alterations of DNA, and chromosomal abnormalities. Neurodevelopmental or neuropsychiatric diseases, including autism—often arise by de novo mutations that usually not present in either of the parents. De novo mutations might occur as early as in the parental germline, during embryonic, fetal development, and/or post-natally, through ageing and life. Mutation timing could lead to mutation burden of less than heterozygosity to approaching homozygosity. Developmental timing of somatic mutation attainment will affect the mutation load and distribution throughout the body. In this review, we discuss the timing of de novo mutations, spanning from mutations in the germ lineage (all ages), to post-zygotic, embryonic, fetal, and post-natal events, through aging to death. These factors can determine the tissue specific distribution and load of de novo mutations, which can affect disease. The disease threshold burden of somatic de novo mutations of a particular gene in any tissue will be important to define.
Collapse
Affiliation(s)
- Mohiuddin Mohiuddin
- Program of Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
- *Correspondence: Mohiuddin Mohiuddin, ; Christopher E. Pearson,
| | - R. Frank Kooy
- Department of Medical Genetics, University of Antwerp, Edegem, Belgium
| | - Christopher E. Pearson
- Program of Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
- *Correspondence: Mohiuddin Mohiuddin, ; Christopher E. Pearson,
| |
Collapse
|
2
|
Tatour Y, Bar-Joseph H, Shalgi R, Ben-Yosef T. Male sterility and reduced female fertility in SCAPER-deficient mice. Hum Mol Genet 2020; 29:2240-2249. [PMID: 32510560 DOI: 10.1093/hmg/ddaa113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/31/2020] [Accepted: 06/01/2020] [Indexed: 11/12/2022] Open
Abstract
Mutations in S-phase cyclin A-associated protein in the endoplasmic reticulum (SCAPER) cause a recessively inherited multisystemic disorder whose main features are retinal degeneration and intellectual disability. SCAPER, originally identified as a cell cycle regulator, was also suggested to be a ciliary protein. Because Scaper mutant males are sterile, we set up to characterize their phenotype. The testes of Scaper mutant mice are significantly smaller than those of WT mice. Histology revealed no signs of spermatogenesis, and seminiferous tubules contained mainly Sertoli cells with a few spermatogonia/spermatogonial stem cells (SSCs). In WT testes, SCAPER is expressed by SSCs and in the various stages of spermatogenesis, as well as in Sertoli cells. In WT spermatozoa SCAPER is not expressed in the flagellum but rather in the head compartment, where it is found both in the nucleus and in the perinuclear region. Scaper mutant females present reduced fertility, manifested by a significantly smaller litter size compared to WT females. Mutant ovaries are similar in size but comprised of significantly less primordial and antral follicles, compared to WT ovaries, while the number of atretic follicles is significantly higher. In WT ovarian follicles SCAPER is expressed in the somatic granulosa cells as well as in the oocyte. In conclusion, our data demonstrate that SCAPER is a crucial component in both male and female reproductive systems. We hypothesize that the reproductive phenotype observed in Scaper mutant mice is rooted in SCAPER's interaction with cyclin A/Cdk2, which play an important role, however different, in male and female gonads.
Collapse
Affiliation(s)
- Yasmin Tatour
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Hadas Bar-Joseph
- The TMCR unit, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Ruth Shalgi
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Tamar Ben-Yosef
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| |
Collapse
|
3
|
Ji HJ, Wang DM, Wu YP, Niu YY, Jia LL, Liu BW, Feng QJ, Feng ML. Wuzi Yanzong pill, a Chinese polyherbal formula, alleviates testicular damage in mice induced by ionizing radiation. Altern Ther Health Med 2016; 16:509. [PMID: 27927244 PMCID: PMC5142375 DOI: 10.1186/s12906-016-1481-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/08/2016] [Indexed: 11/10/2022]
Abstract
BACKGROUND Chinese medicine Wuzi Yanzong pill (WZYZP) was firstly documented in ancient Chinese medical works "She Sheng Zhong Miao Fang" by Shi-Che Zhang in 1550 AD. The traditional herbal formula is widely used in treating nephrasthenia lumbago, prospermia, erectile dysfunction and male sterility. The present study was to explore the effects of WZYZP on ionizing irradiation-induced testicular damage in mice. METHODS The pelvic region of male mice was exposed to X-rays for inducing testicular damage. The effects of WZYZP on testicular damage were evaluated in terms of testes weight, sperm quantity and motility, testes oxidative status and serum hormone levels. The alterations in testicular structure were examined by hematoxylin-eosin staining. Additionally, changes in proliferating cell nuclear antigen (PCNA) expression of testes were explored by western blot. RESULTS Pelvic exposure to x-ray induced reduction in testes weight and sperm quality, along with oxidative stress and abnormal testicular architecture in testes. Oral administration of WZYZP for 3 weeks markedly increased testes weight, sperm quantity and motility, and attenuated testicular architecture damage. Meanwhile, WZYZP treatment significantly reversed the reduction of serum testosterone, and decreased testes malondialdehyde (MDA) and Oxidative stress index (OSI) relative to the radiated mice. Additionally, WZYZP effectively prevented the downregulation of PCNA expression in testes induced by x-ray irradiation. CONCLUSION These findings suggest WZYZP exhibits ameliorating effects against ionizing irradiation-induced testicular damage in mice, which may be related to its antioxidation.
Collapse
|
4
|
Pedroza-Garcia JA, Domenichini S, Mazubert C, Bourge M, White C, Hudik E, Bounon R, Tariq Z, Delannoy E, Del Olmo I, Piñeiro M, Jarillo JA, Bergounioux C, Benhamed M, Raynaud C. Role of the Polymerase ϵ sub-unit DPB2 in DNA replication, cell cycle regulation and DNA damage response in Arabidopsis. Nucleic Acids Res 2016; 44:7251-66. [PMID: 27193996 PMCID: PMC5009731 DOI: 10.1093/nar/gkw449] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/09/2016] [Indexed: 12/24/2022] Open
Abstract
Faithful DNA replication maintains genome stability in dividing cells and from one generation to the next. This is particularly important in plants because the whole plant body and reproductive cells originate from meristematic cells that retain their proliferative capacity throughout the life cycle of the organism. DNA replication involves large sets of proteins whose activity is strictly regulated, and is tightly linked to the DNA damage response to detect and respond to replication errors or defects. Central to this interconnection is the replicative polymerase DNA Polymerase ϵ (Pol ϵ) which participates in DNA replication per se, as well as replication stress response in animals and in yeast. Surprisingly, its function has to date been little explored in plants, and notably its relationship with DNA Damage Response (DDR) has not been investigated. Here, we have studied the role of the largest regulatory sub-unit of Arabidopsis DNA Pol ϵ: DPB2, using an over-expression strategy. We demonstrate that excess accumulation of the protein impairs DNA replication and causes endogenous DNA stress. Furthermore, we show that Pol ϵ dysfunction has contrasting outcomes in vegetative and reproductive cells and leads to the activation of distinct DDR pathways in the two cell types.
Collapse
Affiliation(s)
- José Antonio Pedroza-Garcia
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Séverine Domenichini
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Christelle Mazubert
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Mickael Bourge
- Institute of Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Charles White
- Génétique, Reproduction et Développement, UMR CNRS 6293/Clermont Université/INSERM U1103, 63000 Clermont-Ferrand, France
| | - Elodie Hudik
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Rémi Bounon
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Zakia Tariq
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Etienne Delannoy
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Ivan Del Olmo
- CBGP (INIA-UPM) Departamento de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Madrid 28223, Spain
| | - Manuel Piñeiro
- CBGP (INIA-UPM) Departamento de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Madrid 28223, Spain
| | - Jose Antonio Jarillo
- CBGP (INIA-UPM) Departamento de Biotecnología, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Campus de Montegancedo, Madrid 28223, Spain
| | - Catherine Bergounioux
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Moussa Benhamed
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Cécile Raynaud
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Bâtiment 630, 91405 Orsay, France Institute of Plant Sciences Paris-Saclay IPS2, Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| |
Collapse
|
5
|
Abstract
Due to increased numbers of young cancer patients and improved survival, the impact of anticancer treatments on fertility has become a major health concern. Despite mounting research on ovarian toxicity, there is paucity of data regarding reliable biomarkers of testicular toxicity. Our aim was to evaluate anti-Müllerian hormone (AMH) as a marker for chemotherapy-induced testicular toxicity. Serum AMH and a panel of gonadal hormones were measured in male cancer patients at baseline and after chemotherapy. In the preclinical setting, mice were injected with diverse chemotherapies and were killed 1 week or 1, 3, or 6 months later. We evaluated spermatogenesis by AMH as well as qualitative and quantitative sperm parameters. Nineteen patients were enrolled, the median age was 38 years (21-44 y). Serum AMH was correlated with increased FSH and T and decreased inhibin-B in gonadotoxic protocols (cisplatin or busulfan) and remained unchanged in nongonadotoxic protocols (capecitabine). AMH expression had the same pattern in mice serum and testes; it was negatively correlated with testicular/epididymal weight and sperm motility. The increase in testicular AMH expression was also correlated with elevated apoptosis (terminal transferase-mediated deoxyuridine 5-triphosphate nick-end labeling) and reduced proliferation (Ki67, proliferating cell nuclear antigen; all seminiferous tubules cells were analyzed). Severely damaged mice testes demonstrated a marked costaining of AMH and GATA-4, a Sertoli cell marker; staining that resembled the pattern of the Sertoli cell-only condition. Our study indicates that the pattern of serum AMH expression, in combination with other hormones, can delineate testicular damage, as determined in both experimental settings. Future large-scale clinical studies are warranted to further define the role of AMH as a biomarker for testicular toxicity.
Collapse
Affiliation(s)
- Mattan Levi
- Department of Cell and Developmental Biology (M.L., N.H., R.S.), Sackler Faculty of Medicine, Tel Aviv University, Israel and Institute of Oncology (S.M.S., I.B-A.), Davidoff Center, Rabin Medical Center, Beilinson Campus, Petah-Tiqva 49100, and Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Noa Hasky
- Department of Cell and Developmental Biology (M.L., N.H., R.S.), Sackler Faculty of Medicine, Tel Aviv University, Israel and Institute of Oncology (S.M.S., I.B-A.), Davidoff Center, Rabin Medical Center, Beilinson Campus, Petah-Tiqva 49100, and Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Salomon M Stemmer
- Department of Cell and Developmental Biology (M.L., N.H., R.S.), Sackler Faculty of Medicine, Tel Aviv University, Israel and Institute of Oncology (S.M.S., I.B-A.), Davidoff Center, Rabin Medical Center, Beilinson Campus, Petah-Tiqva 49100, and Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Ruth Shalgi
- Department of Cell and Developmental Biology (M.L., N.H., R.S.), Sackler Faculty of Medicine, Tel Aviv University, Israel and Institute of Oncology (S.M.S., I.B-A.), Davidoff Center, Rabin Medical Center, Beilinson Campus, Petah-Tiqva 49100, and Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Irit Ben-Aharon
- Department of Cell and Developmental Biology (M.L., N.H., R.S.), Sackler Faculty of Medicine, Tel Aviv University, Israel and Institute of Oncology (S.M.S., I.B-A.), Davidoff Center, Rabin Medical Center, Beilinson Campus, Petah-Tiqva 49100, and Sackler Faculty of Medicine, Tel-Aviv University, Israel
| |
Collapse
|
6
|
Levi M, Tzabari M, Savion N, Stemmer SM, Shalgi R, Ben-Aharon I. Dexrazoxane exacerbates doxorubicin-induced testicular toxicity. Reproduction 2015; 150:357-66. [DOI: 10.1530/rep-15-0129] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Infertility induced by anti-cancer treatments pose a major concern for cancer survivors. Doxorubicin (DXR) has been previously shown to exert toxic effects on the testicular germinal epithelium. Based upon the cardioprotective traits of dexrazoxane (DEX), we studied its potential effect in reducing DXR-induced testicular toxicity. Male mice were injected with 5 mg/kg DXR, 100 mg/kg DEX, combination of both or saline (control) and sacrificed either 1, 3 or 6 months later. Testes were excised and further processed. Glutathione and apoptosis assays were performed to determine oxidative stress. Immunohistochemistry and confocal microscopy were used to study the effects of the drugs on testicular histology and on spermatogonial reserve. DXR and the combined treatment induced a striking decline in testicular weight. DEX prevented DXR-induced oxidative stress, but enhanced DXR-induced apoptosis within the testes. Furthermore, the combined treatment depleted the spermatogonial reserve after 1 month, with impaired recovery at 3 and 6 months post-treatment. This resulted in compromised sperm parameters, testicular and epididymal weights as well as significantly reduced sperm motility, all of which were more severe than those observed in DXR-treated mice. The activity of DEX in the testis may differ from its activity in cardiomyocytes. Adding DEX to DXR exacerbates DXR-induced testicular toxicity.
Collapse
|
7
|
Uchimura A, Hidaka Y, Hirabayashi T, Hirabayashi M, Yagi T. DNA polymerase delta is required for early mammalian embryogenesis. PLoS One 2009; 4:e4184. [PMID: 19145245 DOI: 10.1371/journal.pone.0004184] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Accepted: 12/10/2008] [Indexed: 11/23/2022] Open
Abstract
Background In eukaryotic cells, DNA polymerase δ (Polδ), whose catalytic subunit p125 is encoded in the Pold1 gene, plays a central role in chromosomal DNA replication, repair, and recombination. However, the physiological role of the Polδ in mammalian development has not been thoroughly investigated. Methodology/Principal Findings To examine this role, we used a gene targeting strategy to generate two kinds of Pold1 mutant mice: Polδ-null (Pold1−/−) mice and D400A exchanged Polδ (Pold1exo/exo) mice. The D400A exchange caused deficient 3′–5′ exonuclease activity in the Polδ protein. In Polδ-null mice, heterozygous mice developed normally despite a reduction in Pold1 protein quantity. In contrast, homozygous Pold1−/− mice suffered from peri-implantation lethality. Although Pold1−/− blastocysts appeared normal, their in vitro culture showed defects in outgrowth proliferation and DNA synthesis and frequent spontaneous apoptosis, indicating Polδ participates in DNA replication during mouse embryogenesis. In Pold1exo/exo mice, although heterozygous Pold1exo/+ mice were normal and healthy, Pold1exo/exo and Pold1exo/− mice suffered from tumorigenesis. Conclusions These results clearly demonstrate that DNA polymerase δ is essential for mammalian early embryogenesis and that the 3′–5′ exonuclease activity of DNA polymerase δ is dispensable for normal development but necessary to suppress tumorigenesis.
Collapse
|
8
|
Affiliation(s)
- Zachary F Pursell
- Department of Health and Human Services, Laboratory of Molecular Genetics, National Institute of Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
| | | |
Collapse
|
9
|
Rossi P, Lolicato F, Grimaldi P, Dolci S, Di Sauro A, Filipponi D, Geremia R. Transcriptome analysis of differentiating spermatogonia stimulated with kit ligand. Gene Expr Patterns 2007; 8:58-70. [PMID: 18036996 DOI: 10.1016/j.modgep.2007.10.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 10/02/2007] [Accepted: 10/17/2007] [Indexed: 01/15/2023]
Abstract
Kit ligand (KL) is a survival factor and a mitogenic stimulus for differentiating spermatogonia. However, it is not known whether KL also plays a role in the differentiative events that lead to meiotic entry of these cells. We performed a wide genome analysis of difference in gene expression induced by treatment with KL of spermatogonia from 7-day-old mice, using gene chips spanning the whole mouse genome. The analysis revealed that the pattern of RNA expression induced by KL is compatible with the qualitative changes of the cell cycle that occur during the subsequent cell divisions in type A and B spermatogonia, i.e. the progressive lengthening of the S phase and the shortening of the G2/M transition. Moreover, KL up-regulates in differentiating spermatogonia the expression of early meiotic genes (for instance: Lhx8, Nek1, Rnf141, Xrcc3, Tpo1, Tbca, Xrcc2, Mesp1, Phf7, Rtel1), whereas it down-regulates typical spermatogonial markers (for instance: Pole, Ptgs2, Zfpm2, Egr2, Egr3, Gsk3b, Hnrpa1, Fst, Ptch2). Since KL modifies the expression of several genes known to be up-regulated or down-regulated in spermatogonia during the transition from the mitotic to the meiotic cell cycle, these results are consistent with a role of the KL/kit interaction in the induction of their meiotic differentiation.
Collapse
Affiliation(s)
- Pellegrino Rossi
- Dipartimento di Sanita' Pubblica e Biologia Cellulare, Universita' degli Studi di Roma Tor Vergata, via Montpellier 1, 00133 Rome, Italy.
| | | | | | | | | | | | | |
Collapse
|
10
|
Pavlov YI, Shcherbakova PV, Rogozin IB. Roles of DNA Polymerases in Replication, Repair, and Recombination in Eukaryotes. International Review of Cytology 2006; 255:41-132. [PMID: 17178465 DOI: 10.1016/s0074-7696(06)55002-8] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The functioning of the eukaryotic genome depends on efficient and accurate DNA replication and repair. The process of replication is complicated by the ongoing decomposition of DNA and damage of the genome by endogenous and exogenous factors. DNA damage can alter base coding potential resulting in mutations, or block DNA replication, which can lead to double-strand breaks (DSB) and to subsequent chromosome loss. Replication is coordinated with DNA repair systems that operate in cells to remove or tolerate DNA lesions. DNA polymerases can serve as sensors in the cell cycle checkpoint pathways that delay cell division until damaged DNA is repaired and replication is completed. Eukaryotic DNA template-dependent DNA polymerases have different properties adapted to perform an amazingly wide spectrum of DNA transactions. In this review, we discuss the structure, the mechanism, and the evolutionary relationships of DNA polymerases and their possible functions in the replication of intact and damaged chromosomes, DNA damage repair, and recombination.
Collapse
Affiliation(s)
- Youri I Pavlov
- Eppley Institute for Research in Cancer and Allied Diseases, Departments of Biochemistry and Molecular Biology, and Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska 68198-6805, USA
| | | | | |
Collapse
|
11
|
Pinon-Lataillade G, Masson C, Bernardino-Sgherri J, Henriot V, Mauffrey P, Frobert Y, Araneda S, Angulo JF. KIN17 encodes an RNA-binding protein and is expressed during mouse spermatogenesis. J Cell Sci 2005; 117:3691-702. [PMID: 15252136 DOI: 10.1242/jcs.01226] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Genotoxic agents deform DNA structure thus eliciting a complex genetic response allowing recovery and cell survival. The Kin17 gene is up-regulated during this response. This gene encodes a conserved nuclear protein that shares a DNA-binding domain with the bacterial RecA protein. The KIN17 protein binds DNA and displays enhanced expression levels in proliferating cultured cells, suggesting a role in nuclear metabolism. We investigated this by studying the expression profile of KIN17 protein during mouse spermatogenesis. As expected, the expression level of Kin17 is higher in proliferating than in differentiated cells. KIN17 is selectively extracted from this tissue by detergents and a fraction was tightly associated with the nuclear matrix. Germinal cells ubiquitously express Kin17 and the protein is located mainly in the nucleus except in elongated spermatids where cytoplasmic staining is also observed. Sertoli and germ cells that are no longer mitotically active express KIN17, suggesting a general role in all testicular cell types. In adult testis a significant proportion of KIN17 co-purifies with polyadenylated RNA. KIN17 directly binds RNA, preferentially poly(G) and poly(U) homopolymers. These results together with the identification of KIN17 as a component of the human spliceosome indicate that this protein may participate in RNA processing.
Collapse
Affiliation(s)
- Ghislaine Pinon-Lataillade
- Laboratoire de Génétique de la Radiosensibilité, CEA, Direction des Sciences du Vivant, Département de Radiobiologie et de Radiopathologie, B.P. 6, 92265 Fontenay aux Roses CEDEX, France.
| | | | | | | | | | | | | | | |
Collapse
|
12
|
van der Laan R, Uringa EJ, Wassenaar E, Hoogerbrugge JW, Sleddens E, Odijk H, Roest HP, de Boer P, Hoeijmakers JHJ, Grootegoed JA, Baarends WM. Ubiquitin ligase Rad18Sc localizes to the XY body and to other chromosomal regions that are unpaired and transcriptionally silenced during male meiotic prophase. J Cell Sci 2004; 117:5023-33. [PMID: 15383616 DOI: 10.1242/jcs.01368] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In replicative damage bypass (RDB) in yeast, the ubiquitinconjugating enzyme RAD6 interacts with the ubiquitin ligase RAD18. In the mouse, these enzymes are represented by two homologs of RAD6, HR6a and HR6b, and one homolog of RAD18, Rad18Sc. Expression of these genes and the encoded proteins is ubiquitous, but there is relatively high expression in the testis. We have studied the subcellular localization by immunostaining Rad18Sc and other RDB proteins in mouse primary spermatocytes passing through meiotic prophase in spermatogenesis. The highest Rad18Sc protein level is found at pachytene and diplotene, and the protein localizes mainly to the XY body, a subnuclear region that contains the transcriptionally inactivated X and Y chromosomes. In spermatocytes that carry translocations for chromosomes 1 and 13, Rad18Sc protein concentrates on translocation bivalents that are not fully synapsed. The partly synapsed bivalents are often localized in the vicinity of the XY body, and show a very low level of RNA polymerase II, indicating that the chromatin is in a silent configuration similar to transcriptional silencing of the XY body. Thus, Rad18Sc localizes to unsynapsed and silenced chromosome segments during the male meiotic prophase. All known functions of RAD18 in yeast are related to RDB. However, in contrast to Rad18Sc, expression of UBC13 and polη, known to be involved in subsequent steps of RDB, appears to be diminished in the XY body and regions containing the unpaired translocation bivalents. Taken together, these observations suggest that the observed subnuclear localization of Rad18Sc may involve a function outside the context of RDB. This function is probably related to a mechanism that signals the presence of unsynapsed chromosomal regions and subsequently leads to transcriptional silencing of these regions during male meiotic prophase.
Collapse
Affiliation(s)
- Roald van der Laan
- MGC-Department of Cell Biology and Genetics, Center for Biomedical Genetics, Erasmus MC, University Medical Center, PO Box 1738, 3000 DR Rotterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Reini K, Uitto L, Perera D, Moens PB, Freire R, Syväoja JE. TopBP1 localises to centrosomes in mitosis and to chromosome cores in meiosis. Chromosoma 2004; 112:323-30. [PMID: 15138768 DOI: 10.1007/s00412-004-0277-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Accepted: 03/08/2004] [Indexed: 01/24/2023]
Abstract
Topoisomerase IIbeta binding protein 1 (TopBP1), previously shown to localise to sites of DNA damage and to stalled replication forks, has been implicated in DNA replication and in DNA damage response. In this work we showed that TopBP1 was localised in structures other than stalled replication forks. In late mitosis TopBP1 localises to centrosomes in a manner similar to other DNA damage response proteins such as BRCA1 and p53. Spindle checkpoint activation does not affect this centrosomal localisation. Moreover, in the testis, we detected high levels of TopBP1 associated with meiotic prophase chromosome cores and the X-Y pair. Together, these data suggest a direct role of TopBP1 during both mitosis and meiotic prophase I.
Collapse
Affiliation(s)
- Kaarina Reini
- Biocenter Oulu and Department of Biochemistry, P.O. Box 3000, 90014, University of Oulu, Finland
| | | | | | | | | | | |
Collapse
|
14
|
Abstract
Trinucleotide expansions cause at least 30 diseases including Huntington's disease (HD). Many are inherited predominantly through paternal transmissions, which are probably the result of germ-cell-specific mutations. A recent study of testicular germ cells in HD patients revealed that expansions occur in diploid cells before the completion of meiosis. Therefore, expansions are not limited to the late-haploid spermatids, in which the genome is 'sleeping'. These results have implications both for research aimed at understanding the transmission of this serious mutation and for developing new therapies for the disease.
Collapse
Affiliation(s)
- Christopher E Pearson
- Program of Genetics and Genomic Biology, The Hospital for Sick Children, 555 University Avenue, Elm Wing 11-135, Toronto, Ontario, Canada M5G 1X8.
| |
Collapse
|
15
|
Yu Z, Guo R, Ge Y, Ma J, Guan J, Li S, Sun X, Xue S, Han D. Gene expression profiles in different stages of mouse spermatogenic cells during spermatogenesis. Biol Reprod 2003; 69:37-47. [PMID: 12606389 DOI: 10.1095/biolreprod.102.012609] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
During spermatogenesis, diploid stem cells differentiate, undergo meiosis and spermiogenesis, and transform into haploid spermatozoa. Various factors have been demonstrated to regulate this marvelous process of differentiation, but the expression of only a few genes specifically involved in spermatogenesis has been studied. In the present study, different types of spermatogenic cells were isolated from Balb/c mice testes of different ages using the velocity sedimentation method, and we determined the expression profiles of 1176 known mouse genes in six different types of mouse spermatogenic cells (primitive type A spermatogonia, type B spermatogonia, preleptotene spermatocytes, pachytene spermatocytes, round spermatids, and elongating spermatids) using Atlas cDNA arrays. Of the 1176 genes on the Atlas Mouse 1.2 cDNA Expression Arrays, we detected 181 genes in primitive type A spermatogonia, 256 in type B spermatogonia, 221 in preleptotene spermatocytes, 160 in pachytene spermatocytes, 141 in round spermatids, and 126 in elongating spermatids. A number of genes were detected as differential expression (up-regulation or down-regulation). Fourteen of the differentially expressed genes have been further confirmed by reverse transcription-polymerase chain reaction for their expression characterizations in different types of spermatogenic cells. These results provide more information for further studies into spermatogenesis-related genes and may lead to the identification of genes with potential relevance to spermatogenesis.
Collapse
Affiliation(s)
- Zuoren Yu
- Department of Cell Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, China
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Salama N, Tsuji M, Tamura M, Kagawa S. Proliferating cell nuclear antigen in testes of infertile men with varicocele--preliminary results of interrelationship with sperm count before and after varicocelectomy. Scand J Urol Nephrol 2003; 37:48-52. [PMID: 12745744 DOI: 10.1080/00365590310008695] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE This study was conducted to assess germ cell kinetics and correlate them with sperm counts before and after varicocelectomy. MATERIAL AND METHODS Forty-three testicular biopsy specimens were obtained from 47 patients with varicocele during varicocelectomy. Similar specimens were obtained from 8 fertile volunteers. All specimens were immunostained using anti-proliferating cell nuclear antigen (anti-PCNA) antibody. PCNA expression was evaluated by assessing its staining intensity (SI) and labeling index (LI). RESULTS The varicocele specimens revealed significantly lower SI and LI than the controls. There was a significant correlation between initial sperm concentration and LI but not SI. Coexistence of LI > or = 31 and preoperative sperm count > 1 million/ml correlated with a significant rise in the postoperative sperm count. CONCLUSIONS PCNA is a useful molecular marker for assessing germ cell kinetics in varicocele patients. The decline in DNA synthesis, as suggested by the lower PCNA SI and LI in varicocele specimens, could be a reason for the disordered spermatogenesis in these patients. PCNA LI may also be considered as a beneficial clinical marker and may help to predict the surgical outcome after varicocele repair.
Collapse
Affiliation(s)
- Nader Salama
- Department of Urology, Tokushima School of Medicine, Tokushima City, Japan.
| | | | | | | |
Collapse
|
17
|
Takizawa T, Imai T, Mitsumori K, Takagi H, Onodera H, Yasuhara K, Ueda M, Tamura T, Hirose M. Gonadal toxicity of an ethanol extract of Psoralea corylifolia in a rat 90-day repeated dose study. J Toxicol Sci 2002; 27:97-105. [PMID: 12058452 DOI: 10.2131/jts.27.97] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Ethanol extracts of seeds of Psoralea corylifolia are proposed as food additives for processed food preservation. An extract was administered by admixing into diet at concentrations of 0, 0.375, 0.75, 1.5 or 3.0% to 10 male and 10 female F344 rats each for 90 days to evaluate its toxicity. Body weight gain, food consumption and food conversion efficiency (body weight gain per food consumption) were lower in the extract-treated animals, except for the 0.375% males, as compared to the control animals. Absolute and/or relative testes weights in the 1.5 and 3.0% groups and those of ovaries in the 3.0% group were significantly (p < 0.01) lower than in the control group. On histopathological examination, seminiferous tubular atrophy and Leydig cell atrophy in the testes, and epithelial cell atrophy in the seminal vesicles and prostate were observed in the 1.5 and 3.0% males. Decrease in the number of corpora lutea associated with frequent necrotic follicles in the ovaries in the 1.5 and 3.0% females and less frequent endometrial glands in the uterus in the 3.0% females were also detected. These results might suggest disruption of the hypothalamus-pituitary-gonadal axis in Psoralea corylifolia-treated rats as possible mechanisms underlying this gonadal toxicity.
Collapse
Affiliation(s)
- Tamotsu Takizawa
- Division of Pathology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Yazawa T, Yamamoto T, Nakayama Y, Hamada S, Abé S. Conversion from mitosis to meiosis: morphology and expression of proliferating cell nuclear antigen (PCNA) and Dmc1 during newt spermatogenesis. Dev Growth Differ 2000; 42:603-11. [PMID: 11142682 DOI: 10.1046/j.1440-169x.2000.00544.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The conversion from mitosis to meiosis is a phenomenon specific to the cellular progenitors of gametes; however, the mechanism or mechanisms responsible for this conversion are poorly understood. To this end, some morphological and molecular changes that occur during the initiation of meiosis in newt spermatogenesis are reported in the present paper. In situ morphologic studies revealed that spermatogonial stages comprise two phases: early mitotic generations (G1-G4) and late mitotic generations (G5-G8). Morphologic conversion from secondary spermatogonia to primary spermatocytes occurred during the intermediate stage of premeiotic DNA replication. The expression of proliferating cell nuclear antigen (PCNA), a DNA polymerase-delta auxiliary protein, in spermatogonia was weak in G1, highest during DNA synthesis (S), decreased in G2 and was not detectable in dividing cells. Complementary DNA for newt homologs of DMC1 (disrupted meiotic cDNA), which is an Escherichia coli RecA-like protein specifically active during meiosis, were isolated. The newt Dmc1 mRNA was first expressed significantly during the preleptotene stage and this continued into the spermatid stage. These observations present a basis for investigating the mechanism(s) controlling the conversion of newt spermatogonial cells from mitosis to meiosis.
Collapse
Affiliation(s)
- T Yazawa
- Department of Materials and Life Science, Graduate School of Science and Technology, Kumamoto University, Japan
| | | | | | | | | |
Collapse
|
19
|
Hazzouri M, Pivot-Pajot C, Faure AK, Usson Y, Pelletier R, Sèle B, Khochbin S, Rousseaux S. Regulated hyperacetylation of core histones during mouse spermatogenesis: involvement of histone deacetylases. Eur J Cell Biol 2000; 79:950-60. [PMID: 11152286 DOI: 10.1078/0171-9335-00123] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Here we report a detailed analysis of waves of histone acetylation that occurs throughout spermatogenesis in mouse. Our data showed that spermatogonia and preleptotene spermatocytes contained acetylated core histones H2A, H2B and H4, whereas no acetylated histones were observed throughout meiosis in leptotene or pachytene spermatocytes. Histones remained unacetylated in most round spermatids. Acetylated forms of H2A and H2B, H3 and H4 reappeared in step 9 to 11 elongating spermatids, and disappeared later in condensing spermatids. The spatial distribution pattern of acetylated H4 within the spermatids nuclei, analyzed in 3D by immunofluorescence combined with confocal microscopy, showed a spatial sequence of events tightly associated with chromatin condensation. In order to gain an insight into mechanisms controlling histone hyperacetylation during spermiogenesis, we treated spermatogenic cells with a histone deacetylase inhibitor, trichostatin A (TSA), which showed a spectacular increase of histone acetylation in round spermatids. This observation suggests that deacetylases are responsible for maintaining a deacetylated state of histones in these cells. TSA treatment could not induce histone acetylation in condensing spermatids, suggesting that acetylated core histones are replaced by transition proteins without being previously deacetylated. Moreover, our data showed a dramatic decrease in histone deacetylases in condensing spermatids. Therefore, the regulation of histone deacetylase activity/concentration appears to play a major role in controling histone hyperacetylation and probably histone replacement during spermiogenesis.
Collapse
Affiliation(s)
- M Hazzouri
- Unite INSERM U309, UJF Grenoble, Institut Albert Bonniot, Domaine de la Merci, France
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Huang D, Knuuti R, Palosaari H, Pospiech H, Syväoja JE. cDNA and structural organization of the gene Pole1 for the mouse DNA polymerase epsilon catalytic subunit. Biochim Biophys Acta 1999; 1445:363-71. [PMID: 10366722 DOI: 10.1016/s0167-4781(99)00058-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cDNA and the gene for the mouse DNA polymerase epsilon catalytic subunit were cloned. The deduced protein sequence shows remarkable evolutionary conservation in DNA polymerase epsilon family. However, several conserved elements involved in template-primer binding differ from those of other class B polymerases. This is likely to reflect a distinctive function of the enzyme. The gene that was assigned to chromosome 5 region E3-E5, consists of 49 exons and has a non-conforming splice site in the junction of exon and intron 13. A CpG island covers the promoter region which contains several putative consensus elements critical for S phase upregulated and serum responsive promoters.
Collapse
Affiliation(s)
- D Huang
- Biocenter Oulu and Department of Biochemistry, University of Oulu, FIN-90570, Oulu, Finland
| | | | | | | | | |
Collapse
|
21
|
Jokela M, Mäkiniemi M, Lehtonen S, Szpirer C, Hellman U, Syväoja JE. The small subunits of human and mouse DNA polymerase epsilon are homologous to the second largest subunit of the yeast Saccharomyces cerevisiae DNA polymerase epsilon. Nucleic Acids Res 1998; 26:730-4. [PMID: 9443964 PMCID: PMC147316 DOI: 10.1093/nar/26.3.730] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Human DNA polymerase epsilon is composed of a 261 kDa catalytic polypeptide and a 55 kDa small subunit of unknown function. cDNAs encoding the small subunit of human and mouse DNA polymerase epsilon were cloned. The predicted polypeptides have molecular masses of 59.469 and 59.319 kDa respectively and they are 90% identical. The human and mouse polypeptides show 22% identity with the 80 kDa subunit of the five subunit DNA polymerase epsilon from the yeast Saccharomyces cerevisiae. The high degree of conservation suggests that the 55 kDa subunit shares an essential function with the yeast 80 kDa subunit, which was earlier suggested to be involved in S phase cell cycle control in a pathway that is able to sense and signal incomplete replication. The small subunits of human and mouse DNA polymerase epsilon also show homology to the C-terminal domain of the second largest subunit of DNA polymerase alpha. The gene for the small subunit of human DNA polymerase epsilon (POLE2) was localized to chromosome 14q21-q22 by fluorescence in situ hybridization.
Collapse
Affiliation(s)
- M Jokela
- Biocenter Oulu and Department of Biochemistry, University of Oulu, FIN-90570 Oulu, Finland
| | | | | | | | | | | |
Collapse
|